Telomeres are the functional units on chromosome ends that provide stability to eukaryotic chromosomes. Telomere length is maintained by an equilibrium of shortening and lengthening activities. In the past few years there have been major advances in our understanding of the roles of telomerase, telomere binding proteins, recombination, and telomere processing activities that affect telomere length. In addition, recent progress has been made towards an understanding how the telomeric nucleoprotein complex allows cells to distinguish natural chromosome ends from broken DNA and how telomeres protect chromosome ends from degradation and end-to-end fusion. This new research on telomeres and telomerase has generated significant interest in telomere biology from in a variety of fields including molecular biology, human genetics, aging and cancer. Because the telomere field is attracting researchers from a variety of different backgrounds, it is an appropriate time to have a meeting focused exclusively on telomere biology. A number of leaders in the telomere field have agreed to chair sessions at the meeting and we hope to attract leaders from related fields as well as new people who may have a fresh perspective on important issues that are now confronting the telomere field. The format of Cold Spring Harbor meetings, where almost all talks are chosen from submitted abstracts, maximizes the opportunity of new researchers and young investigators to present their most recent unpublished work.